VOLATILE ORGANIC COMPOUNDS OF HYBRID RUGOSA ROSES IN LATVIA

Hybrid Rugosa is the most winter hardy group of roses in the climatic conditions of the Baltic Sea region. This study aimed at identifying new qualities of Hybrid Rugosa by focusing on determina- tion of content of volatile organic compounds of flower petals and in hydrosols produced from these. Volatiles of seven cultivars were extracted using solid phase microextraction (SPME) with subsequent separation by gas chromatography. Identification was made by comparison with mass spectral libraries and by calculating linear retention indexes and comparing them with litera- ture data. Twenty-five volatile aroma compounds were identified in the petals and hydrosols of six Hybrid Rugosa and species. Among those, phenylethylalcohol, ß-citronellol, geraniol and nerol were predominant. Species Rosa rugosa and variety Plena showed the highest total level of volatiles and contained 26% and 31% ß-citronellol, respectively. Varieties Raita and Sniedze contained up to 57% citronellol. The main volatile compounds were detected in hydrosols in the same proportions, but their concentration was higher than in petals. The varieties Raita and Vi- oleta , bred in Latvia, are recommendable for use as a source of hydrosol.